The invention relates to the finishing of magnetic pot or cup cores made of ferrite which are used to make up inductors used in big series in telecommunications equipment.
Such inductors are formed by at least one winding which is placed inside a magnetic pot consisting of half-pots assembled joining their open side and having a center portion designed to be machined to create a given air gap for the pot assembly which depends on the required inductance value.
Depending on the applications this value may also be adjusted by providing the centre section of the half-pot with an annular shape receiving a screw-in magnetic slug core designed to enter the gap to a greater or lesser extent.
It has already been proposed in French Pat. No. 2 293 047 by this applicant, for pots of the side opening type, to machine the air gap by tangential attack by the grinding wheel, and notably by applying a machine comprising an endless belt for housing and carrying the half-pots, subjected to pressure means pressing the side edges of the latter onto a reference plane with respect to which the grinding wheel projects through a suitable opening.
However this kind of machine is unsuited to the execution of various small or medium runs (several thousands) corresponding to various pot shapes and dimensions, since the time for changing the set-up, particularly the belt, then turns out to be relatively substantial, as do the adjustments required for the desired machining accuracies, which lead, in particular, to sacrificing a certain number of parts. Similarly, machining is performed with no immediate visual check and any ferrite breakage incident may affect the finish of a certain series of parts before this can be noticed or remedied.